It has become commonplace for landowners to light their properties with in-ground landscape lights. Typically, the lights are installed in a series along driveways, walkways, and other areas sought to be lighted. In use, landscape lights provide pleasant illumination which improves the safety, appearance, and security of properties which employ them.
However, landscape lights serve no useful purpose in daylight. Furthermore, during daylight hours many consider the lights as marring the appearance of the well kept lawns on which they are situated. Also, it is during daylight hours when the lights are unnecessary that people are likely to be working or playing outdoors, and the lights present potentially dangerous obstacles to trip over or fall on. In addition, landscape lights act as highly undesirable obstacles to those seeking to maintain the lawn. Of course, the problems which upstanding lights present to people are supplemented by the problems which people present to the lights in the form of damage and inadvertent movement.
Fortunately, the prior art includes landscape lights which have the ability of selectively telescoping between an extended position above the ground for providing illumination and a retracted position level with the ground for avoiding obtrusiveness. Sundry means have been disclosed for extending and retracting the lighted portion of such landscape lights. For example, there have been landscape lights raised by complex gearing arrangements, lights raised by solenoids, and even lights raised by springs which are selectively deformable by the manipulation of temperature. These lights have been complex, expensive, prone to mechanical trouble, and difficult to repair.
Such inventive lights appear to have descended from the Bivens' "Retractable Light Fixture," found in U.S. Pat. No. 4,180,850. That patent discloses a telescoping landscape light hydraulically raised by water. Although laudable for its relative simplicity, the Bivens light left a multiplicity of problems which subsequent inventors have attempted to correct. The most notable problem is the tendency of water to freeze. In addition to rendering the lighting system completely inoperable, water's freezing within the light device or the hoses leading thereto could cause severe and permanent damage to the system.
Considering the above-described state of the art, one sees that the relatively simple, hydraulically raised landscape lights have limited applicability in cooler climates while the more universally applicable lights are undesirably complex. In light of the above, it becomes clear that there is a real need for an extensible and retractable landscape light which combines simplicity of design and durability of use with universal functionality.